Microbiological quality of high-demand foods from three major cities in Ecuador

Authors: SALAZAR-LLORENTE, ENRIQUE - Escuela Superior Politecnica Del Litoral; MORALES, MARIA - Escuela Superior Politecnica Del Litoral; SORNOZA, IVETTE - Escuela Superior Politecnica Del Litoral; MARIDUENA-ZAVALA, MARIA GABRIELA - Escuela Superior Politecnica Del Litoral; Gu, Ganyu; Nou, Xiangwu; ORTIZ, JOHANA - Universidad Del Azuay, Facultad De Cincia Y Tecnoligia; MALDONADO-ALVARADO, PEDRO - Escuela Superior Politecnica Del Litoral; MANUAL CEVALLOS, JUAN - Escuela Superior Politecnica Del Litoral

Submitted to: International Journal of Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/7/2020
Publication Date: 9/11/2020
Citation: Salazar-Llorente, E., Morales, M., Sornoza, I., Mariduena-Zavala, M., Gu, G., Nou, X., Ortiz, J., Maldonado-Alvarado, P., Manual Cevallos, J. 2020. Microbiological quality of high-demand foods from three major cities in Ecuador. International Journal of Food Microbiology. https://doi.org/10.4315/JFP-20-271.
DOI: https://doi.org/10.4315/JFP-20-271

Interpretive Summary: Ecuador is a developing country in urgent needs of establishing national food safety policies and regulations, which require baseline data on the microbial quality of Ecuadorian food. With assistance from ARS scientist, Ecuadorian scientists sampled and analyzed a large number of samples in 10 groups of high-demand Ecuadorian food, and conducted microbiological analyses for the presence of foodborne pathogens. This work provided baseline data for the microbiological quality of major foods in Ecuador that will be incorporated in food safety policy development. As US is a major importer of Ecuadorian agriculture products, this work also contribute to USDA objectives of promoting international food safety.

Technical Abstract: Bacterial foodborne diseases are one of the most important public health issues worldwide but in Ecuador reports on the microbiological quality of foods are scarce. In this study, a total of 450 samples of high-demand Ecuadorian food, including bolon, encebollado, sauces, ceviche, fruits, fruit juices, fruit salads, cheese, raw chicken and ground beef were collected from popular street markets in the cities of Guayaquil, Quito and Cuenca. Populations of total aerobic mesophilic bacteria (TAM), total coliforms (TC), fecal coliforms (FC), Escherichia coli (EC), Salmonella enterica and Listeria monocytogenes were examined on composited samples by plate count following the local regulations (Norma Tecnica Ecuatoriana - INEN) for each kind of food. Random colonies from each culture were identified using Biolog OmniLog ID and sequencing of the V3-V4 region on the 16S rRNA gene. Average TAM, TC, FC and EC levels were 5.10 ± 0.12, 2.50 ± 0.16, 1.09 ± 0.12 and 0.83 ± 0.12 log CFU/g or mL, respectively, with significant variations among the cities. The prevalence of Salmonella in chicken and sauces as well as L. monocytogenes in cheese and fruit salad was greater than 20 %. Opportunistic pathogens including Klebsiella pneumoniae, Staphylococcus sciuri, and Enterococcus spp. were frequently identified in the samples from all three cities. High prevalence of spoilage microorganisms such as Bacillus amyloliquefaciens and biocontrol bacteria such as Lactococcus lactis was also observed. This is the first report on the microbiological quality of food from Ecuador.